This invention relates in general to industrial baghouses and more particularly to a baghouse housing constructed with integral wall stiffeners.
Continuous emphasis on environmental quality has resulted in considerable importance being attached to the control of industrial emissions. One technique that has proven highly effective in controlling air pollution has been the separation of undesirable particulate matter from a gas stream by fabric filtration.
Such filtration is carried out in dust collection apparatus known in the trade as a "baghouse" that operates on the same general principle as an ordinary vacuum cleaner, except on a much larger scale. The baghouse includes a sheet metal housing that is divided by one or more tube sheets into two chambers referred to as plenums. Disposed in openings in the tube sheet are fabric filters. A particle laden gas stream is passed initially into one chamber (the dirty gas plenum) where dust accumulates on the fabric filter as the gas flows through the fabric into the other chamber (the clean gas plenum) and out of the unit through an exhaust duct.
Although all baghouses are constructed in accordance with the foregoing principles, there are numerous operational and structural differences among the various types of baghouses. The present invention is applicable to any variety of baghouse and the type described and depicted herein is merely representative of the use of the invention in a typical baghouse.
In a typical baghouse, filtration occurs from the outside to the inside of each bag. In this type of baghouse, referred to as an outside bag collector, the dirty and clean gas plenums are separated by the tube sheet and the filter bags are suspended from the tube sheet. An exhaust duct is connected to the clean gas plenum and located within the exhaust duct is a fan or other similar means for creating a gas current through the baghouse. The fan creates an air current or "pull" through the baghouse. The particle laden gas enters the dirty gas plenum through an inlet, and passes through the filters and into the clean gas plenum. The resulting clean gas is drawn out through the exhaust duct. The gas current through the baghouse creates a negative pressure within the baghouse. This negative pressure creates stress on the housing of the baghouse, especially the dirty gas plenum walls.
Also creating stress on the baghouse housing walls is external wind loads. The baghouse housing walls are exposed to the elements of nature and must be structurally strong enough to withstand the pressure forced upon it by wind. The structure must be of sufficient strength so that the walls of the baghouse are not destroyed or deformed by external wind.
As can obviously be seen, the same problem would exist in a baghouse that forces gas through the baghouse by creating a positive pressure within the baghouse. This positive pressure would also create stress on the baghouse walls.
In order to alleviate this stress on the baghouse walls, and to keep the walls from "buckling in" under the negative pressure, baghouses built before the onset of the present invention have employed separate wall stiffeners to support the housing walls. These wall stiffeners generally take the shape of a tubular or angular channel piece of steel that is interspersed along the inner or outer wall of the housing to act as support beams. The baghouse housing wall of this type of baghouse typically consisted of a plurality of flat upright panels of sheet metal welded together to form the "box-like" housing. These separate wall stiffeners were then welded to the wall at appropriate intervals along the wall. This method requires numerous welds to hold the housing together, one at each end of each panel to join it with the next adjoining panel and at least two additional welds to secure the separate stiffener to the wall. This method of supporting the walls also requires the fabrication of two separate elements to form the wall; the flat panels and the stiffener piece. This multitude of welds and the requirement of fabricating two separate parts to construct a baghouse housing wall strong enough to withstand the pressure applied to it is costly and inefficient. Thus, there is a need for a baghouse that is structurally strong enough to withstand the pressure inherent in a baghouse and that is also cost effective and efficient. It is a primary goal of the present invention to provide such a baghouse.
More specifically, it is an object of the invention to provide a baghouse that provides structural rigidity in an economical manner.
Another object of the invention is to provide a baghouse housing wall where only a single type of panel, all being of a uniform shape, is required to both construct the housing walls and to provide the stiffening element.
An additional object of the invention is to provide a baghouse housing wall where fewer welds are required to construct the wall thereby reducing cost and increasing efficiency.
A further object of the invention is to provide a baghouse where the stiffening element is integral with the wall.
A still further object of the invention is to provide a baghouse where the housing wall is constructed with individual panels each shaped generally in an elongated "U" so that when the panels are arranged in a "side-by-side" manner a channel is created between each adjoining panel that serves as the stiffening element for the wall.
Other and further objects of the invention, together with the features of novelty appurtenant thereto, will appear in the course of the following description.